Alternative Fuel
Supporting advanced nuclear power while reducing a national liability
Oklo is in advanced talks with the U.S. government to receive a portion of its stockpile of surplus plutonium to use as reactor fuel for fast fission power plants. This material would help bridge the gap between the limited near-term supply of domestic high-assay low-enriched uranium (HALEU) fuel and future availability of HALEU and recycled fuel, while safely, securely, and responsibly reducing a long-term national liability.
A legacy material with a modern role
The U.S. holds plutonium that is no longer required for defense purposes and has been set aside for disposal. Previous national approaches have included diluting and disposing of it or converting it into mixed oxide fuel for conventional reactors. However, these efforts have faced high costs, delays, and other practical challenges.
Fast reactors offer another pathway
These reactors’ fast-neutron spectrum is well suited to using plutonium-bearing fuel, allowing them to produce abundant, clean electricity while consuming the plutonium through fission.
Fuel fabrication
The plutonium will be subject to strict material controls required by the U.S. Department of Energy and the U.S. Nuclear Regulatory Commission to prevent risks of theft or diversion during transport and fabrication.
Deployment in Aurora powerhouses
Fuel is used in 75 MWe Aurora powerhouse units.
Effectively destroyed through fission
Most plutonium atoms are split during operation.
Managed materials
The remaining material is reduced in volume from its original state, radiotoxic for less time, and subject to stringent material management requirements.
Strengthening fuel security while generating power
Limited near-term domestic fuel availability is the primary constraint on ambitions to accelerate advanced nuclear deployment in the U.S., achieve energy independence, and end reliance on foreign fuel supply. Surplus plutonium, an energy-rich resource, already exists and has been designated for disposal. Its disposal would waste a powerful fuel source that could generate low-cost, reliable power while domestic HALEU production and commercial recycling capabilities mature.
Fuel from existing U.S. surplus plutonium provides a limited, near-term option to supplement Oklo’s broader, long-term multi-path fuel strategy. Oklo’s future reactors will be fueled primarily by HALEU and recycled used nuclear fuel, with the option to use other existing surplus plutonium stocks if they become available. Oklo’s fuel strategy does not depend on any new separation of plutonium in the U.S. or globally.
Safety, security, and safeguards
Any use of plutonium must reduce risk rather than create new risks. Using surplus plutonium for reactor fuel has the immediate nonproliferation and nuclear security benefit of drawing down global stockpiles of separated plutonium, a long-term goal of the U.S. and the international community.
The material will be handled, transported, fabricated, stored, and used in accordance with federal safety, security, safeguards, material control, and transportation requirements, using existing government infrastructure, where viable, and with all costs borne by Oklo. This approach couples private investment with commercial reactor deployment to support the government’s disposition objectives, strengthen the domestic nuclear fuel supply, and generate electricity to support growing energy needs.
